Selective calling system for radio telephone system - repeats call to moving subscriber if latter fails to acknowledge first call to reduce engaged time

摘要

The selective calling system has non-moving subscribers calling moving subscribers who acknowledge receipt of the call. If no acknowledgement is given the call is repeated. The selective calls are sent consecutively in a given time frame that such calling is repeated one or more frame sections after the call was first sent. The frame section and the duration of a selective call are of equal size. An unacknowledged call is repeated at most twice. The advantage lies in reducing the time for which a subscriber is engaged without a connection being established.